So far, I have not read about placement of clock in the bedroom.
However, my personal view, to hang a clock in front of the bed may not be ideal coz the bed is a restful place. Hanging the clock in front of the bed.. i.e. with the clock facing oneself whiel sleeping... uhm... may not be helpful in gettting a restful sleep.
However, besides the bed, such as an alarm clock, which is small and convenient to access, guess that's no harm.
At most, just get 'irritated' that the alarm rings in the morning.
Food for thought... .
Well, if I do come across... will let you know.